So, I am new to the forums so I'll start this off by giving you details on the bike and explaining what I have done up to this point.

2012 XL1200N
V&H Shor Shots Staggered Exhaust
Stock Intake
V&H FP3
1" Tank Lift
Wire Tuck
Coil relocated between V with equidistant plug wires
NGK Iridium Plugs

The Problem:
Running out to cabbage patch fro bike week back in March the bike started losing power and threw codes P1352 and P1354 (codes pointing to front cylinder coil)
I limped the bike home on just the rear cylinder, and because the codes pointed to the coil I ordered a new one.
New coil arrives, I ohm out both coils and they both give very similar results but I go ahead and throw the new coil on (I have not tried to start the bike again at this point). Fire it up and it runs great until it warms up and then back to firing on just the rear cylinder again.
I let the bike cool and swapped back to the stock coil out of curiosity, fire it up and it runs great until it warms up and then back to banging on rear cylinder only.
Work gets needy and I dont have time to revisit for a while.
Fast forward to a few weeks ago
Finally get time to work on it again so I start checking connections and wires, swapped the plugs so the plug from the rear is in the front and front plug is in the rear, no dice same result. Compression on both cylinders was very close so I don't think that was the issue.
Pulled the injectors and hooked them to a tester, they cycle like they should and I go ahead and clean them out on the test rig and reinstall everything, still doing the same thing.
I notice when I pull up sensor data on the bike while its running on one cylinder that it is showing an engine temp of 388 degrees, mind you at this point the bike has only been running for about 10 minutes, check with IR Thermometer and get about 230*F not 388.
Swap out ETS for good measure, have intake off, run bike around block several times, runs great. reassemble everything.
Run to gas station a couple miles away, fill up, return home. No problems.
Go to take bike on a night ride the same night and let it idle about 10 minutes while talking to someone, jump on bike and prepare to take off and BAM front cylinder shuts off on me temp at that time 314*F.
Start bike this morning, runs on both cylinders for about 2 minutes and then drops down to one again, temp reading 230 at the time of the cylinder drop.
Currently only reading the P1352 code for the front coil driver.

Any ideas on what else to check?
Im at a loss and really hoping it isn't an issue with the ECM and don't want to tow it to Harley until I have exhausted all possibilities other than the ECM.

 

After googling and coming up with a couple of threads from this forum the posters came to the conclusion the fault lay between the ecm and the coil. If not a wiring problem caused by tank lift and wire tuck then new ecm.

https://www.hdforums.com/forum/sport...ght-p1352.html

https://www.hdforums.com/forum/sport...ocation-2.html

 

Thanks for the info!
I read those posts, the problem is when you read them through their entirety no one ever confirms the actual problem, they only speculate that they believe they found the solution and never came back and confirmed what their problem was. That is why I asked, I read several posts on the forum and nobody ever confirms a solution and I have already done most of the tests that I have been able to find that were suggested on the threads I read. I am getting voltage to the coil both cold and hot, I have tested pins A and B on the harness coming to the coil after the bike started limping and got the same results I got when it was cold. It is just so intermittent that I am not entirely certain if it is a loose pin in a connector that isn't having an issue with the bike not running due to a lack of vibration, or if the ecu is getting hot from heat emitting off the rear cylinder and it is causing a malfunction. If the ecu has an issue I want to know what caused it as well so that I can try to mitigate the possibility of another failure in the future. Should I relocate it to a cooler location, or is it just a known weak point in the ECU circuitry that cannot be mitigated without extensive electronics knowledge?

Need some root cause failure analysis.

Thinking on it more it almost seems like the ECU may be kicking out an overcurrent or overvoltage on more than one system since I had an ETS go bad as well. Unfortunately there really isn't a way to tell what caused my ETS to fail at this point because there are only 2 faults that can come from the ETS and neither ever popped. I suppose if I knew the voltage it should be getting I could deduce if I was getting the wrong power at the connector.

I guess I will see about yanking the ECU out and testing it. Just gotta see if I can locate the testing parameters for it. Do you know if there is a thread with the diagrams and testing parameters for the ecu pin out and harness on here somewhere already?

 

Also I feel like it is worth mentioning that the problem did not arise immediately after the coil relocation and wire tuck. I put about 1000 miles on the bike after those modifications were done before the problem popped up. I did however wire the power to a kill switch that I hid on the bike after someone attempted to steal it and ruined my ignition cylinder, that wiring happened the day before the problem popped up.

 

Sounds like you diagnosed your problem. I would start by removing that switch and wiring as per factory, just to test it and see.